The duo finished regulation tied at 9-under-par 275 after Bohn bogeyed each of his last two holes to open the door for Carter.
'When I realized I was in the playoff I was really pumped,' said Carter, who carded a final-round 70. 'It all happened so quickly. I was lucky to get up and down on the last hole of regulation.'
Back at the par-5 18th to start the playoff, Carter sent his second shot over the green into the back rough while Bohn's approach fell in a bunker short of the putting surface.
Bohn was unlucky with his bunker shot, however. His blast went through the green, bounced off a camera and rolled back in front of the trap. Bohn hit another chip onto the green and this time missed he missed the par putt coming back.
Carter landed his third shot on the green and took two putts for the decisive par and his maiden victory on the Nationwide Tour.
'I've put in a lot of work over the years so getting my first win is huge,' said Carter. 'I've been close out here the past few years, so to finally do it is huge.'
Carter started the day two shots behind Bohn at DiamondBack Golf Club and parred his first four holes before an eagle at the par-5 fifth. He made the turn at 10-under but found trouble early on the inward half with a double-bogey at the par-4 10th.
He recovered with a birdie at the 11th but followed that up with a bogey at the 14th. The 35-year-old tallied a birdie at the closing par-5 and turned to wait for Bohn, who was falling apart down the stretch.
Bohn collected two birdies over his first nine holes and a birdie at the 11th put him three shots clear of the field. It was all downhill from the point on, however, with four bogeys over his last seven holes.
'To bogey 17 and 18 knowing all I needed was one par is disappointing,' said Bohn, who managed a 1-over 72 in the final round. 'I missed a couple of shorts putts which was probably my nerves. I got a little tense but that is golf.'
Blaine McCallister, who won this year's NE Pennsylvania Classic, posted a final-round 68 to finish alone in third at 8-under-par 276.
Scott Dunlap, Kelly Gibson, Steve Ford, Derek Gillespie and Jaxon Brigman finished one shot further back at 7-under-par 277.